Aiming at the problems of unbalanced investment structure and insufficient means of resource allocation in distribution network investment allocation, a bi-level allocation method for distribution network investment decision based on multi-indicator system and reward coefficient is proposed. Considering the needs of investment allocation calculation and input-output efficiency evaluation, the distribution network investment allocation index system and input-output index system are constructed based on the basic indexes of distribution network investment evaluation. The index weights are determined based on the comprehensive subject-objective assignment method combining hierarchical analysis and variance coefficient method, and the index scores are calculated using interval triangular fuzzy affiliation theory. The reward coefficients are introduced to further characterize the relationship between investment allocation and input-output. The relationship between investment allocation and input-output is further portrayed by the introduction of reward coefficients, and a bi-level allocation model of "province-to-city" and "city-to-county" distribution network investment decision is established based on the combined scores of the two. Finally, the results show that the model constructed in this paper can improve the scientificity of distribution network investment allocation.